Answer:
m∠D = 29°
Step-by-step explanation:
First, notice that ΔSTU and ΔDEF are similar triangles.
For instance, for side ST and DE, the scale factor is:
Likewise, for TU and EF and SU and DF, the scale factor reamins that same:
By SSS Similarity, ΔSTU ~ ΔDEF.
Note that our similarity statement states that ∠S corresponds to ∠D.
So, ∠S = ∠D.
Since the angles remain the same in a scaled factor and ∠S measures 29°, ∠D is also 29°.